1. Field of the Invention
This invention relates to a heat developable light-sensitive material and especially with a heat developable light-sensitive material having an overcoat layer of a polymer.
In accordance with the present invention, there is provided a heat developable light-sensitive material comprising, on a support member, (1) an organic silver salt, (2) a light-sensitive silver halide or a light-sensitive silver halide prepared by reacting an organic silver salt with a halide in situ, (3) a reducing agent, (4) a polymeric binder and (5) an overcoat layer comprising a polymer.
2. Description of the Prior Art
Photographic processes using a silver halide, giving a better sensitivity and gradient than the electrophotographic process and the diazotype photographic process, have been most commonly used. However, the silver halide light-sensitive material used for such processes is developed with a developing solution and then subjected to several processings such as stopping, fixing, water washing and stabilizing in order to protect the developed image from discoloring and fading under normal light as well as to protect the undeveloped areas (which will hereinafter be referred to as "back-ground") from blackening. Therefore, such photographic processes take much time and labor and are subject to some problems, e.g., the chemicals used are injurious to humans and harmful to the work area, and often workers' hands and clothing are injured. In photographic processes using a silver halide, therefore, it has been desired that the processing be carried out in a dry state without solution processing, and the processed image be kept stable.
To reach this end, much effort has been expended to provide suitable methods. One method is the so-called mono bath development and fixing method wherein the two processings of development and fixing in an ordinary photographic process are finished in one processing, which is mentioned in U.S. Pat. No. 2,875,048, British Pat. No. 954,453 and German Pat. No. 1,163,142. A second method contemplates converting the wet processings in an ordinary silver halide photographic process into dry processings as disclosed in German Pat. No. 1,174,159, and British Pat. Nos. 943,476 and 951,644. A third method is to use a light-sensitive element consisting of a silver salt of a long chain aliphatic carboxylic acid such as behenic acid, the silver salt of saccharin or the silver salt of benzotriazole, and a catalytic amount of a silver halide, as disclosed in Japanese patent publication Nos. 4921/1968, 4924/1968, 26582/1969, 18416/1970, 12700/1970 and 22185/1970 and British Pat. No. 1,205,500.